Business Portal 5.1 - Purchase Request - Error message is blank

Hi,

I've installed GP Biz Portal and when I click on "Purchase Request", the screen flashes briefly with the fields, then a message says:

I've checked my company setup for requisition (numbering, approval hierarchy) all seems fine. The only thing I can think off is installing the patches for SharePoint Foundation 2010.

Am I missing something else?

Thanks in advance and Regards

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